diff options
Diffstat (limited to 'src/tokenizer.rs')
| -rw-r--r-- | src/tokenizer.rs | 239 |
1 files changed, 0 insertions, 239 deletions
diff --git a/src/tokenizer.rs b/src/tokenizer.rs deleted file mode 100644 index 7d887e4..0000000 --- a/src/tokenizer.rs +++ /dev/null @@ -1,239 +0,0 @@ -use std::mem::take; -use crate::*; - -#[derive(PartialEq)] -enum StringLiteral { - None, - Raw, - NullTerminated, -} - -pub struct TokenIterator { - /// The characters that comprise the program souce code. - chars: Vec<char>, - /// The index of the next character to read. - i: usize, - /// The address of the next character to read. - addr: CharAddress, - /// If true, skip over any whitespace characters. If false, stop reading - /// when a whitespace character is encountered. - skip_whitespace: bool, - /// The name of the most recently defined label. - label: String, - /// If not None, each individual character will be tokenised as a ByteLiteral. - parse_string_literal: StringLiteral, - - - /// The address of the first character of the current token. - start: CharAddress, - /// The address of the final character of the current token. - end: CharAddress, - /// The entire current token. - source: String, - /// The first character of the current token. - prefix: char, - /// The second and remaining characters of the current token. - suffix: String, -} - -impl TokenIterator { - /// Create an iterator from a string of program source code. - pub fn from_str(source_code: &str) -> Self { - Self { - chars: source_code.chars().collect(), - i: 0, - addr: CharAddress::zero(), - skip_whitespace: true, - parse_string_literal: StringLiteral::None, - label: String::new(), - start: CharAddress::zero(), - end: CharAddress::zero(), - source: String::new(), - prefix: ' ', - suffix: String::new(), - } - } - /// Append a character to the current token. - fn push(&mut self, c:char) { - self.end = self.addr; - self.source.push(c); - self.suffix.push(c); - self.next(c); - } - /// Move forward to the next source character. - fn next(&mut self, c: char) { - self.addr.column += 1; - self.i += 1; - if c == '\n' { - self.addr.column = 0; - self.addr.line += 1; - } - } - /// Mark the current character as being the first character of a new token. - fn mark_start(&mut self, c:char) { - if c == '"' { - self.parse_string_literal = StringLiteral::NullTerminated; - } else if c == '\'' { - self.parse_string_literal = StringLiteral::Raw; - } else { - self.start=self.addr; - self.end=self.addr; - self.prefix=c; - self.source.push(c); - self.skip_whitespace=false; - } - self.next(c); - } -} - -impl Iterator for TokenIterator { - type Item = SyntacticToken; - - fn next(&mut self) -> Option<SyntacticToken> { - // Initialise values before reading the next token - let mut is_comment = false; - self.skip_whitespace = true; - - // Iterate over source characters until a full token is read - while let Some(c) = self.chars.get(self.i) { - let c = *c; - // Parse individual characters from a string literal - if self.parse_string_literal != StringLiteral::None { - if c == '"' && self.parse_string_literal == StringLiteral::NullTerminated { - self.parse_string_literal = StringLiteral::None; - let token = SyntacticToken { - r#type: SyntacticTokenType::ByteLiteral(0), - source_location: SourceLocation { - source: c.to_string(), start:self.addr, end:self.addr }, - error: None, - }; - self.next(c); - return Some(token); - } else if c == '\'' && self.parse_string_literal == StringLiteral::Raw { - self.parse_string_literal = StringLiteral::None; - self.next(c); - continue - } else { - self.next(c); - return Some(SyntacticToken { - r#type: SyntacticTokenType::ByteLiteral(c as u8), - source_location: SourceLocation { - source: c.to_string(), start:self.addr, end:self.addr }, - error: None, - }); - } - } - // Intercept comments - if is_comment { - self.push(c); if c == ')' { break } else { continue }; } - else if self.skip_whitespace && c == '(' { - is_comment = true; self.mark_start(c); continue } - - // Allow a semicolon at the end of a token to be handled as a separate token - if self.source.len() > 0 && c == ';' { break } - // Handle the current character - match (is_whitespace(c), self.skip_whitespace) { - (true, true) => self.next(c), // c is the expected leading whitespace - (false, true) => self.mark_start(c), // c is the first character of the token - (false, false) => self.push(c), // c is a character of the token - (true, false) => break, // c is trailing whitespace - } - // Allow literal values to be chained to the end of the previous token - if self.source.len() > 0 && c == ':' { break } - } - - // If no source characters were grabbed then we have read through the entire source file - if self.source.len() == 0 { return None; } - // Allow handling macro terminators and symbols of length 1 in the match expression - if self.suffix.len() == 0 { self.prefix = '\0'; } - // Consume the collected characters to be used in the match expression - let full = take(&mut self.source); - let suffix = take(&mut self.suffix); - let mut error = None; - let mut parse_padding_value = |v| { - parse_short(v).or_else(|| { - error = Some(Error::InvalidPaddingValue); Some(0) - }).unwrap() - }; - - let r#type = match self.prefix { - '(' => { SyntacticTokenType::Comment } - '@' => { SyntacticTokenType::LabelDefinition({self.label=suffix.clone(); suffix}) } - '&' => { SyntacticTokenType::LabelDefinition(format!("{}/{}", self.label, suffix)) } - '$' => { SyntacticTokenType::Padding(parse_padding_value(&suffix)) } - '~' => { SyntacticTokenType::Reference(format!("{}/{}", self.label, suffix)) } - '%' => if let Some(("", sublabel)) = suffix.split_once("~") { - SyntacticTokenType::MacroDefinition(format!("{}/{}", self.label, sublabel)) - } else { - SyntacticTokenType::MacroDefinition(suffix) - } - _ => { - if ";" == &full { SyntacticTokenType::MacroDefinitionTerminator } - else if let Some(value) = parse_byte_lit(&full) { SyntacticTokenType::ByteLiteral(value) } - else if let Some(value) = parse_short_lit(&full) { SyntacticTokenType::ShortLiteral(value) } - else if let Some(value) = parse_instruction(&full) { SyntacticTokenType::Instruction(value) } - else { SyntacticTokenType::Reference(full.clone()) } - } - }; - Some(SyntacticToken { - r#type, - source_location:SourceLocation::new(full,self.start,self.end), - error, - }) - } -} - - -fn parse_byte_lit(token: &str) -> Option<u8> { - match token.len() { 2 => u8::from_str_radix(token, 16).ok(), _ => None } } -fn parse_short_lit(token: &str) -> Option<u16> { - match token.len() { 4 => u16::from_str_radix(token, 16).ok(), _ => None } } -fn parse_short(token: &str) -> Option<u16> { - match token.len() { 1..=4 => u16::from_str_radix(token, 16).ok(), _ => None } } -fn is_whitespace(c: char) -> bool { - match c { ' '|'\t'|'\n'|'\r'|'['|']'|'(' =>true, _=>false } } -fn parse_instruction(token: &str) -> Option<u8> { - Some(match token { - // Flow control operators - "HLT"=>0x00,"DBG" =>0x20,"NOP" =>0x80, // The remaining op-codes in this line are unclaimed - "JMP"=>0x01,"JSR" =>0x21,"JMP:" =>0x41,"JSR:" =>0x61,"JMPr" =>0x81,"JSRr" =>0xA1,"JMPr:" =>0xC1,"JSRr:" =>0xE1, - "JCN"=>0x02,"JSN" =>0x22,"JCN:" =>0x42,"JSN:" =>0x62,"JCNr" =>0x82,"JSNr" =>0xA2,"JCNr:" =>0xC2,"JSNr:" =>0xE2, - "JKN"=>0x03,"JKN*"=>0x23,"JKN:" =>0x43,"JKN*:"=>0x63,"JKNr" =>0x83,"JKNr*"=>0xA3,"JKNr:" =>0xC3,"JKNr*:"=>0xE3, - // Relational operators - "EQU"=>0x04,"EQU*"=>0x24,"EQU:"=>0x44,"EQU*:"=>0x64,"EQUr"=>0x84,"EQUr*"=>0xA4,"EQUr:"=>0xC4,"EQUr*:"=>0xE4, - "NKQ"=>0x05,"NKQ*"=>0x25,"NKQ:"=>0x45,"NKQ*:"=>0x65,"NKQr"=>0x85,"NKQr*"=>0xA5,"NKQr:"=>0xC5,"NKQr*:"=>0xE5, - "LTH"=>0x06,"LTH*"=>0x26,"LTH:"=>0x46,"LTH*:"=>0x66,"LTHr"=>0x86,"LTHr*"=>0xA6,"LTHr:"=>0xC6,"LTHr*:"=>0xE6, - "GTH"=>0x07,"GTH*"=>0x27,"GTH:"=>0x47,"GTH*:"=>0x67,"GTHr"=>0x87,"GTHr*"=>0xA7,"GTHr:"=>0xC7,"GTHr*:"=>0xE7, - // Memory operators - "LDA"=>0x08,"LDA*"=>0x28,"LDA:"=>0x48,"LDA*:"=>0x68,"LDAr"=>0x88,"LDAr*"=>0xA8,"LDAr:"=>0xC8,"LDAr*:"=>0xE8, - "LKA"=>0x09,"LKA*"=>0x29,"LKA:"=>0x49,"LKA*:"=>0x69,"LKAr"=>0x89,"LKAr*"=>0xA9,"LKAr:"=>0xC9,"LKAr*:"=>0xE9, - "STA"=>0x0A,"STA*"=>0x2A,"STA:"=>0x4A,"STA*:"=>0x6A,"STAr"=>0x8A,"STAr*"=>0xAA,"STAr:"=>0xCA,"STAr*:"=>0xEA, - "SKA"=>0x0B,"SKA*"=>0x2B,"SKA:"=>0x4B,"SKA*:"=>0x6B,"SKAr"=>0x8B,"SKAr*"=>0xAB,"SKAr:"=>0xCB,"SKAr*:"=>0xEB, - // Device operators - "LDD"=>0x0C,"LDD*"=>0x2C,"LDD:"=>0x4C,"LDD*:"=>0x6C,"LDDr"=>0x8C,"LDDr*"=>0xAC,"LDDr:"=>0xCC,"LDDr*:"=>0xEC, - "LKD"=>0x0D,"LKD*"=>0x2D,"LKD:"=>0x4D,"LKD*:"=>0x6D,"LKDr"=>0x8D,"LKDr*"=>0xAD,"LKDr:"=>0xCD,"LKDr*:"=>0xED, - "STD"=>0x0E,"STD*"=>0x2E,"STD:"=>0x4E,"STD*:"=>0x6E,"STDr"=>0x8E,"STDr*"=>0xAE,"STDr:"=>0xCE,"STDr*:"=>0xEE, - "SKD"=>0x0F,"SKD*"=>0x2F,"SKD:"=>0x4F,"SKD*:"=>0x6F,"SKDr"=>0x8F,"SKDr*"=>0xAF,"SKDr:"=>0xCF,"SKDr*:"=>0xEF, - // - "PSH"=>0x10,"PSH*"=>0x30,"PSH:"=>0x50,"PSH*:"=>0x70,"PSHr"=>0x90,"PSHr*"=>0xB0,"PSHr:"=>0xD0,"PSHr*:"=>0xF0, - "POP"=>0x11,"POP*"=>0x31,"POP:"=>0x51,"POP*:"=>0x71,"POPr"=>0x91,"POPr*"=>0xB1,"POPr:"=>0xD1,"POPr*:"=>0xF1, - "SHF"=>0x12,"SHF*"=>0x32,"SHF:"=>0x52,"SHF*:"=>0x72,"SHFr"=>0x92,"SHFr*"=>0xB2,"SHFr:"=>0xD2,"SHFr*:"=>0xF2, - "SHC"=>0x13,"SHC*"=>0x33,"SHC:"=>0x53,"SHC*:"=>0x73,"SHCr"=>0x93,"SHCr*"=>0xB3,"SHCr:"=>0xD3,"SHCr*:"=>0xF3, - // Stack operators - "SWP"=>0x14,"SWP*"=>0x34,"SWP:"=>0x54,"SWP*:"=>0x74,"SWPr"=>0x94,"SWPr*"=>0xB4,"SWPr:"=>0xD4,"SWPr*:"=>0xF4, - "ROT"=>0x15,"ROT*"=>0x35,"ROT:"=>0x55,"ROT*:"=>0x75,"ROTr"=>0x95,"ROTr*"=>0xB5,"ROTr:"=>0xD5,"ROTr*:"=>0xF5, - "DUP"=>0x16,"DUP*"=>0x36,"DUP:"=>0x56,"DUP*:"=>0x76,"DUPr"=>0x96,"DUPr*"=>0xB6,"DUPr:"=>0xD6,"DUPr*:"=>0xF6, - "OVR"=>0x17,"OVR*"=>0x37,"OVR:"=>0x57,"OVR*:"=>0x77,"OVRr"=>0x97,"OVRr*"=>0xB7,"OVRr:"=>0xD7,"OVRr*:"=>0xF7, - // Arithmetic operators - "ADD"=>0x18,"ADD*"=>0x38,"ADD:"=>0x58,"ADD*:"=>0x78,"ADDr"=>0x98,"ADDr*"=>0xB8,"ADDr:"=>0xD8,"ADDr*:"=>0xF8, - "SUB"=>0x19,"SUB*"=>0x39,"SUB:"=>0x59,"SUB*:"=>0x79,"SUBr"=>0x99,"SUBr*"=>0xB9,"SUBr:"=>0xD9,"SUBr*:"=>0xF9, - "INC"=>0x1A,"INC*"=>0x3A,"INC:"=>0x5A,"INC*:"=>0x7A,"INCr"=>0x9A,"INCr*"=>0xBA,"INCr:"=>0xDA,"INCr*:"=>0xFA, - "DEC"=>0x1B,"DEC*"=>0x3B,"DEC:"=>0x5B,"DEC*:"=>0x7B,"DECr"=>0x9B,"DECr*"=>0xBB,"DECr:"=>0xDB,"DECr*:"=>0xFB, - // Logical operators - "NOT"=>0x1C,"NOT*"=>0x3C,"NOT:"=>0x5C,"NOT*:"=>0x7C,"NOTr"=>0x9C,"NOTr*"=>0xBC,"NOTr:"=>0xDC,"NOTr*:"=>0xFC, - "AND"=>0x1D,"AND*"=>0x3D,"AND:"=>0x5D,"AND*:"=>0x7D,"ANDr"=>0x9D,"ANDr*"=>0xBD,"ANDr:"=>0xDD,"ANDr*:"=>0xFD, - "IOR"=>0x1E,"IOR*"=>0x3E,"IOR:"=>0x5E,"IOR*:"=>0x7E,"IORr"=>0x9E,"IORr*"=>0xBE,"IORr:"=>0xDE,"IORr*:"=>0xFE, - "XOR"=>0x1F,"XOR*"=>0x3F,"XOR:"=>0x5F,"XOR*:"=>0x7F,"XORr"=>0x9F,"XORr*"=>0xBF,"XORr:"=>0xDF,"XORr*:"=>0xFF, - _ => return None, - }) -} |